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How fast can a 12V 4aH sealed led acid battery discharge to house ground? The battery positive to earth ground and the battery negative not connected to anything?

I JUST burned my fingers testing an idea and when I disconnected the positive from 24V battery and connected it to the positive of a 12V there was TREMENDOUS heat at the metal clip I was holding. I quickly moved it away. no wires were burned through. I DID have an experiment going at the time, so the positive connected to the signal gen. The gen is fine with no damage.

Thoughts on the cause of this?? it was VERY unexpected.

Gen is plugged into 5v transformer supply then plugged into the AC house outlet.

How fast can a 12V 4aH sealed led acid battery discharge to house ground? The battery positive to earth ground and the battery negative not connected to anything?

I JUST burned my fingers testing an idea and when I disconnected the positive from 24V battery and connected it to the positive of a 12V there was TREMENDOUS heat at the metal clip I was holding. I quickly moved it away. no wires were burned through. I DID have an experiment going at the time, so the positive connected to the signal gen. The gen is fine with no damage.

Thoughts on the cause of this?? it was VERY unexpected.

Gen is plugged into 5v transformer supply then plugged into the AC house outlet.

Thanks!

Bruce

Energy flows between different potentials. I wrote a small essay here first, but then I thought it is important for the people to realize for themselves.

People wonder where energy comes from? Well it is everywhere. Has been since the Big Bang, since you cannot destroy it. So no worriers there

DISCLAIMER: I do not recommend people to modify their house electrical systems in any way, since that might be lethal ie. do not become the ground wire!

Well this time I tried to purposely repeat what I had done the other day, except I put the analog amp meter on the positive leg and nothing. No heat and smoke like before on the alligator clip, nothing at all..The oddest thing but oh well.

Cheap chinese square wave generator with adjustable duty cycle and frequency , a mosfet driver and proper n-channel mosfet rated at 600V some amps ? Plus a custom made boost converter maybe even adjustable 100-500V but output current would be rather poor (1A at 500V is already 500W!)

Cheap chinese square wave generator with adjustable duty cycle and frequency , a mosfet driver and proper n-channel mosfet rated at 600V some amps ? Plus a custom made boost converter maybe even adjustable 100-500V but output current would be rather poor (1A at 500V is already 500W!)

Hi forest,

Thank you for the reply. I'm not worried about output current rating. Just need the high voltage is all. I was hoping a chip that could produce a square wave but with a very high voltage rating. Like a 555 on steroids...lol

Is there any such chip out there? I've been unable to find one. Sadly. Vacuum tubes would have been great for the high voltage. The things I could do with that...LOL

Hi e2matrix and thank you for the reply. HV pulses don't work hardly at all unfortunately. I need preferably a square wave at 50% duty cycle. Sine wave does work but not as well for my application. I may need to settle for a sine wave but it will need to be high frequency.

A 555 timer has a very low max voltage in. Unfortunately. I do need good rise and fall times on the square wave.

Or perhaps some sort of square wave amplifier? Again, I have been unable to find one.

Hi Bruce, I may be wrong on this but I would think a function generator could turn an SSR on and off with a square wave output to the SSR. Then hook a 500 vdc supply to the other side of the SSR and you should get a 500 volt square wave and duty cycle would depend on the function generator setting. I'm not sure what frequency you need and I don't know how fast an SSR can run but it would surely be faster than a mechanical relay. I haven't tried anything like this so I may be way off in thinking this could work. It might need some additional parts like a HV transistor circuit on the output to achieve what you want. Some of the electronic design forums or hobby electronic forums may be able to help with this if no one else here jumps in for an idea.

One of these attached to a function generator would likely do the job: http://flce.se/But I'd expect they are quite expensive.

First you must choose the voltage. If you need 100 or 500 that's fine , but if you need adjustable then it's more difficult. NExt step is to build or find a power source which can give you this DC voltage. The rest is easy 555 circuit with a mosfet driver and any N-mosfet rated at 600V or more with some protective snubber.You can find someone who create it for you or build yourself because there is plenty of examples online. The most hard part is to make a DC-DC converter to step up from say 12VDC to 500VDC. 300VDC looks easier as you can use existing example from net , for example based on sg3525 chip.This guy has some very good explanation http://tahmidmc.blogspot.com/2013/01/using-sg3525-pwm-controller-explanation.htmlLong time ago based on his detailed info I have built DC-DC converter with 300VDC output (but only some milliamps unfortunately)